[molpro-user] EOM-CCSD second moments

[Joseph Lane]

I am having some difficulty understanding the one-electron properties  
calculated with EOM-CCSD in molpro as compared to the CCSD linear response  
in Dalton. I realise that the EOM-CCSD properties are calculated as  
expectation and the linear response as energy derivatives, hence there  
should be small numeric differences between the two.

For ground state calculations, the dipole moments and quadrupole moments  
calculated with both methods are the same, however the second moments are  
different.

Molpro:

  !CCSD_nonrel dipole moment      :      0.00000000     0.00000000     
-0.64447126

  !CCSD(NOREL) expec  <1.1|QMXX|1.1>     2.937794363335
  !CCSD(NOREL) expec  <1.1|QMYY|1.1>    -3.662513450822
  !CCSD(NOREL) expec  <1.1|QMZZ|1.1>     0.724719087487
  !CCSD(NOREL) expec  <1.1|QMRR|1.1>   -53.392633597836

  !CCSD(NOREL) expec    <1.1|XX|1.1>   -15.839014957055
  !CCSD(NOREL) expec    <1.1|YY|1.1>   -20.239220166494
  !CCSD(NOREL) expec    <1.1|ZZ|1.1>   -17.314398474288

Dalton:

Total Molecular Dipole Moment
                                au             Debye
                    z     -0.64448139     -1.63810812

Total Molecular quadrupole moment

                     X              Y              Z
                Column   1     Column   2     Column   3
        1       2.93725559     0.00000000     0.00000000
        2       0.00000000    -3.66309263     0.00000000
        3       0.00000000     0.00000000     0.72583703


Electronic second moment of charge

                     X              Y              Z

        1      15.83901789     0.00000000     0.00000000
        2       0.00000000   107.37034240     0.00000000
        3       0.00000000     0.00000000    32.24924174


For excited state calculations, the dipole moments are again the same with  
both codes but the quadrupole and second moments are completely different.



Any help would be greatly appreciated.







-- 
Joseph Lane
Department of Chemistry
University of Otago
P.O. Box 56
Dunedin, New Zealand
ph +64 3 479 5378
email : jlane at alkali.otago.ac.nz